GB1348305A - Grinding wheel - Google Patents

Abstract

1348305 Abrasive tools M C SHAW 19 April 1971 [15 April 1970] 26986/71 Heading B3D A grinding wheel assembly comprises a plurality of grinding wheel segments 56, Fig. 2, arranged about the periphery of a wheel in a recess 50 whose opposed side walls 46, 48 converge towards one another in a radially outward direction and co-operate with complementary side faces on the segments or on wedge members abutting the side faces of the segments, such that centrifugal force during rotation of the wheel produces at at least one of said side walls a resultant force having an axial component which produces a compressive clamping force in the grinding segments, the segments (and the members, if present) being spaced from the bottom of the recess whereby substantially no compression clamping force can be applied to the segments prior to rotation of the wheel. The opposed side walls 46, 48 are formed on annular members 40, 44 which are spaced apart by a member 42 and secured together by bolts, the spring member having a thickness such that the side walls, when the assembly is stationary, do not clamp against the segments but apply a compressive clamping force due to centrifugal force acting on the segments when the assembly is rotating. As described, the assembly has twelve segments 56, each of which has a trapezoidal cross-section, and the segments may have the same or different abrasive and may be separated by dummy segments. The annular members 40, 44 and spacer 42 are received between opposed faces 34, 36 on a disc 16 secured to a drive shaft 12 and a disc 27 keyed to the shaft and clamped towards disc 16 by a nut 24. In another embodiment, a wheel member 70, Fig. 5, is secured to a shaft 72 and its rim has a recess formed with opposed side walls 82, 84 which converge towards one another in a radially outward direction. The side walls engage wedge members 92, 94 which are urged radially outwards by resilient 0-rings 97, 98, 100 and have planar surfaces 96 engaging planar surfaces of grinding segments 86 of rectangular cross-section. The 0-rings, or screws (114, Fig. 8, not shown) of another embodiment, act on the wedges so that they apply an initial clamping force when the wheel is stationary. In a further embodiment, one of the side walls is perpendicular to the axis of the shaft and wedges are only provided at one side of the segments. Flange members 102, 104 may be secured to the sides of the member 70 to form troughs 106, 108 for coolant which can pass through passages 110, 111 and gaps between the grinding segments to their operation surfaces.